Visually similar to Mycena pura but the yellowing base is fairly strange.
KOH yellow/gold on gills, becoming opaque; UV light purple/lilac patches on cap, base yellowish/gold; odor mild, sweet; fruiting body dried to lilac/purple.
Western white pine wood near snow. K orange
Some of the gills were serrated, but others were not.
Growing on damp concrete steps. Caps to 40 mm across.
fruiting from wood
Growing of rotten stump